From patchwork Mon Apr 5 21:14:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Fix losing locks during fork Date: Mon, 05 Apr 2010 11:14:35 -0000 From: piastry@etersoft.ru X-Patchwork-Id: 49444 Message-Id: <201004060114.36019.piastry@etersoft.ru> To: linux-cifs-client@lists.samba.org From: Pavel Shilovsky When process does fork() private_data of files with lock list stays the same for file descriptors of the parent and of the child. That's why the parent can't unlock previously before fork() locked region after the child process finished. While finishing the child closes files and deletes locks from the list even if unlocking fails. When the child process finishes the parent doesn't have lock in lock list and can't unlock previously before fork() locked region after the child process finished. This patch provides behaviour to save locks in lock list if unlocking fails. --- fs/cifs/file.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/cifs/file.c b/fs/cifs/file.c index c34b7f8..7185cd3 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -898,9 +898,10 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock) 1, 0, li->type, false); if (stored_rc) rc = stored_rc; - - list_del(&li->llist); - kfree(li); + else { + list_del(&li->llist); + kfree(li); + } } } mutex_unlock(&fid->lock_mutex);